1. Field of the Invention
The invention relates to a device for processing of a strip-shaped workpiece, which device transports and processes a strip-shaped workpiece. The invention relates especially to a device for processing of a strip-shaped workpiece in which the operation of a delivery reel and/or a take-up reel can be carried out without problems even in the case in which the strip-shaped workpiece has through openings when a mask pattern is exposed onto the strip-shaped workpiece.
2. Description of the Related Art
In a device which transports and processes a strip-shaped workpiece (hereinafter also called a xe2x80x9cworkpiecexe2x80x9d) generally a method is used in which a strip-shaped workpiece is pulled off a delivery reel which supplies it, positioned in a processing part of the device at the desired position, and is wound onto a take-up reel. Hereinafter, a continuous workpiece with a great length, such as a rolled film of organic compound, foil metal or the like, is called a xe2x80x9cstrip-shaped workpiecexe2x80x9d.
In one such processing device, there are cases in which, between the delivery reel and the processing part, and between the processing part and the take-up reel, there is a dip of the workpiece in which part of the strip-shaped workpiece sags, i.e., the length of the workpiece between the delivery reel and first guide roller is longer than the distance between them so that the workpiece sags between them. The reason for producing this sag is to keep the tension which is exerted on the strip-shaped workpiece constant, and to adjust for the changes in diameter of the workpiece being unwound off of the delivery reel and wound onto the take-up reel, and to transport the workpiece in the processing part with high stop positioning accuracy. In this way, the transport of the strip-shaped workpiece and operation of the delivery reel and the take-up reel can be carried out independently of one another.
The strip-shaped workpiece is transported by a transport roller located downstream of the processing part in terms of transport together with a pressure roller clamping and turning the workpiece. The delivery reel and the take-up reel are operated such that the length of the strip-shaped workpiece is determined in the dips by sensors and based on these determination signals the rotation and stopping of the reels are controlled. Japanese patent disclosure document HEI 2-100036 describes a device for exposing a strip-shaped workpiece which is provided with the above described dips.
FIG. 6 shows the arrangement of a transport system for a strip-shaped workpiece which is provided with the above described dips. In the figure, a delivery reel 1 is wound with a strip-shaped workpiece W. The strip-shaped workpiece W is delivered by the delivery reel 1 which is driven by a drive device 25, sent via a first dip A and the guide roller 3 to a processing part 10 and subjected to processing.
Transporting of the strip-shaped workpiece W is carried out by a pressure roller 5 and a transport roller 6 which are each located upstream and downstream of the transport direction of a carrier 15 of the processing part 10. The strip-shaped workpiece W is sent by a drive control of the transport roller 6 onto the carrier 15 of the exposure part 10 which is downstream in the transport direction at a set position.
In the processing part 10, there are, for example, a lamp 11 which emits light which contains UV light, a reflector 12, a condenser lens 13, a mask M with a mask pattern, a projection lens 14 and the like. The light which contains UV light and which is emitted by the lamp 11 is reflected by the reflector 12 and is emitted via the condenser lens 13, the mask M and the projection lens 14 onto the strip-shaped workpiece on the carrier 15. Thus the mask pattern of the mask M is exposed on the strip-shaped workpiece W. The above described processing part is hereinafter also called the xe2x80x9cexposure partxe2x80x9d. After completion of exposure, the strip-shaped workpiece W is wound via a guide roller 4 and a second dip B onto a take-up reel 2 which is driven by a drive device 26.
Determination of the strip-shaped workpiece Win dips A and B and operation on the delivery side and the take-up side as shown in FIG. 6 are shown and is described briefly below.
The strip-shaped workpiece W is determined using pairs of sensors of the transmission type 21, 22; 23, 24 which are located one above the other, i.e. at two vertically spaced points of each of the dips A and B.
In the above described sensors of the transmission type 21, 22; 23, 24, the emission elements 21a, 22a, 23a, 24a belong to one group and the light receiving elements 21b, 22b, 23b, and 24b belong to one group. When the sensor light emitted by the emission elements 21a, 22a, 23a, 24a is shielded by the strip-shaped workpiece Wand is not received by the light receiving elements 21b, 22b, 23b, 24b, it is determined that the strip-shaped workpiece W is located between the two elements. Hereinafter, the sensors 21, 23 are called the xe2x80x9cupper sensorsxe2x80x9d and the sensors 22, 24 are called the xe2x80x9clowerxe2x80x9d sensors. Furthermore, the state in which the light receiving elements 21b, 22b, 23b, 24b of sensors 21, 22, 23 and 24 are not shielded by the strip-shaped workpiece W is called xe2x80x9ctransmissionxe2x80x9d and the state in which they are shielded by the strip-shaped workpiece W is called xe2x80x9cshieldingxe2x80x9d.
(1) Control of the delivery reel
Using FIGS. 7(a) to 7(f), control of a conventional delivery reel is described. FIGS. 7(a) to 7(f) show part on the delivery or takeoff side shown in FIG. 6. The strip-shaped workpiece W is transported by the transport roller 6 shown in FIG. 6 in the direction toward the exposure part 10 which is located on the right side in the figure.
(a) As is shown in FIG. 7(a), the delivery reel 1 turns and begins to deliver the strip-shaped workpiece W and the amount of sagging of the strip-shaped workpiece W is small so that both the upper sensor 21 and also the lower sensor 22 of the dip A are in the transmission state. In this state, the strip-shaped workpiece W is allowed to sag in the dip A.
(b) The delivery reel 1 turns and the strip-shaped workpiece W shields the upper sensor 21, as shown in FIG. 7(b), the delivery reel 1 continues to turn.
(c) As is shown in FIG. 7(c), the strip-shaped workpiece W shields the upper sensor 21 and the lower sensor 22. When this state occurs, the delivery reel 1 stops rotation and delivery of the strip-shaped workpiece W.
(d) As is shown in FIG. 7(d), the strip-shaped workpiece W continues to be transported so that the lower sensor 22 is shifted into the transmission state, while the upper sensor 21 is still located in the shielding state. The delivery reel 1 continues the state in which its rotation is stopped.
(e) As is shown in FIG. 7(e), as the strip-shaped workpiece W continues to be transported, both the upper sensor 21 and also the lower sensor 22 are shifted into the transmission state (in the same state as the state described above in 7(a)), the delivery reel 1 again turns and delivery of the strip-shaped workpiece W begins again.
(f) The state which is shown in FIG. 7(f), in which transmission takes place to the upper sensor 21 but the lower sensor 22 is shielded is one that cannot properly occur when the strip-shaped workpiece W is being transported normally. Occurrence of this state is presumably produced because the lower sensor 22 is shielded by scrap and foreign bodies (hereinafter called xe2x80x9cbarrierxe2x80x9d). The rotation of the delivery reel 1 and the transport and processing of the strip-shaped workpiece W are therefore stopped and a fault indication is output.
The above described control is summarized below using Table 1.
(2) Control of the Take-Up Reel
Using FIGS. 8(a) to 8(f), control of a conventional take-up reel is described. FIGS. 8(a) to 8(f) show part of the take-up side shown in FIG. 6. The strip-shaped workpiece W is transported from the exposure part 10 to the right by the transport roller 6; in FIG. 6, the exposure part is located on the left side of the take-up side.
(a) As is shown in FIG. 8(a), the upper sensor 23 and the lower sensor 24 are located in the dip B in the transmission state and the take-up reel 2 is stopped. The strip-shaped workpiece W is transported after completion of exposure by the exposure part 10 and delivered to the dip B.
(b) When the strip-shaped workpiece is being delivered, the strip-shaped workpiece W shields the upper sensor 23, as is shown in FIG. 8(b). The take-up reel 1 remains stopped.
(c) As is shown in FIG. 8(c), the strip-shaped workpiece W shields the upper sensor 23 and the lower sensor 24. The take-up reel 2 begins to turn and take up the strip-shaped workpiece W.
(d) As is shown in FIG. 8(d), the strip-shaped workpiece W is taken up and the lower sensor 24 is shifted into the transmission state. The upper sensor 23 is in the shielding state. The take-up reel 2 continues to turn.
(e) As is shown in FIG. 8(e), the strip-shaped workpiece W continues to be taken up. When both the upper sensor 23 and also the lower sensor 24 are shifted into the transmission state (in the same state as the state described above in (a)), the take-up reel 22 stops turning.
(f) Here, it can be imagined that the state which is shown in FIG. 8(f) and in which transmission to the upper sensor 23 takes place and the lower sensor 24 is shielded is caused by shielding of the lower sensor 24 by a barrier. It is assumed that there cannot properly be this state, as described above relative to the delivery side. Rotation of the take-up reel 2 and transport and processing of the strip-shaped workpiece Ware therefore stopped and a fault indication is output.
The above described control is summarized below using Table 2.
Both on the above described delivery side and also on the above described take-up side, the operation of the reels is called xe2x80x9ccontinuation of previous operationxe2x80x9d when the upper sensor is in the shielding state and the lower sensor is in the transmission state. When the upper sensor is in the transmission state and the lower sensor is in the shielding state, operation of the reels is called xe2x80x9cstopping of operation due to a problem.xe2x80x9d
As was described above, in the transport system shown in FIG. 6, the transport of the strip-shaped workpiece for processing by the transport roller 6, delivery of the delivery reel 1 and take-up of the take-up reel 2 are carried out independently of one another.
There are cases in which the strip-shaped workpiece W has through openings which are called xe2x80x9cdevice holes.xe2x80x9d FIG. 9 shows one example of a strip-shaped workpiece W with device holes. As FIG. 9 shows, in the strip-shaped workpiece W there are device holes Wd and perforation holes Ph which are used, for example, for transport of the strip-shaped workpiece W. In the areas which are provided with device holes Wd, various devices are installed in a later process. Using these through openings, wiring is connected and devices are installed.
The device holes Wd are through openings and therefore pass sensor light. In the dips A and B which are shown in FIG. 6, there are therefore cases in which, depending on the length of the sag of the strip-shaped workpiece W and depending on the pitch with which the device holes Wd are provided, the sensor light passes through the through openings, and in which the existence of the strip-shaped workpiece W cannot be determined even if it is present.
There are, for example, the following cases:
The light from the upper sensors 21, 23 passes through the device holes Wd and a transmission state is determined; and
The light from the lower sensors 22, 24 is shielded by the area outside the device holes Wd and a shielding state is determined.
In this case the above described conventional device indicates a fault and stops treatment even if transport could be carried out without problems.
The above described defect is eliminated when the sensors 21, 24 are positioned at locations which are not provided with device holes Wd, for example, at locations at which the peripheral area of the strip-shaped workpiece W is determined. The shape and the size of the device holes Wd are however different depending on the pattern formed in the strip-shaped workpiece W, such as a circuit pattern or the like, and there are very many patterns thereof.
Therefore, according to the pattern the positions of the sensors 21 to 24 must be changed in the dip, by which a working step is required each time. Furthermore, at the positions at which the sensors 21 to 24 are attached, artificial faults often creep in. Therefore, practical execution is difficult.
The invention was devised to eliminate the above described defects in the prior art.
The object of the invention is achieve in a device for processing a strip-shaped workpiece in which:
a strip-shaped workpiece is provided with a dip, which has been formed by sagging of a strip-shaped workpiece, between the delivery reel and the processing part, and between the processing part and take-up reel;
the length of the dips is determined;
the strip-shaped workpiece is delivered by one reel and taken up by one reel; and
a device is provided for driving the delivery reel;
an upper sensor and a lower sensor are located on top of one another at two locations of the dips; and
moreover, regardless of the above described delivery and the above described take-up, transport and processing of the strip-shaped workpiece are performed so as to enable the transport of the strip-shaped workpiece, its delivery by a reel and its take-up onto a reel to be continued even if the strip-shaped workpiece has partial through openings, such as device holes or the like, and even if sensor light passes through the above described through holes.
by the following being done in accordance with the invention:
(1) generally, a control element carries out processing and transport of the strip-shaped workpiece with a preset frequency when the upper sensor has determined the absence of the workpiece, and the lower sensor has determined the presence of the workpiece, and which detects a fault and interrupts processing and transport when the workpiece determination state by the above described upper sensor and the above described lower sensor does not change during the interval during which the above described processing and the above described transport are carried out.
The delivery reel is controlled as follows by the above described control element.
(a) In the case of a strip-shaped workpiece with through openings, there is not always a barrier in the optical path of the lower sensor, as was described above, even if in the dip transmission of the upper sensor and shielding of the lower sensor were determined. In this case, the device is therefore not immediately considered xe2x80x9cdisrupted,xe2x80x9d but is considered xe2x80x9cin a fault reservation statexe2x80x9d. The strip-shaped workpiece is processed and transported with a preset frequency, for example three times.
(b) When, during the above described interval, the determination state of the strip-shaped workpiece by the above described upper sensor and the above described lower sensor does not change, the device is considered xe2x80x9cfaultyxe2x80x9d and operation of the device is stopped.
(c) If at any time during the above described interval the states of the upper sensor and of the lower sensor change, at this point the xe2x80x9cfault reservation statexe2x80x9d is canceled. Only afterwards, based on the determination signals of the sensors is operation of the delivery reel controlled. This means that the length and the position of the strip-shaped workpiece in the dip change during the intervals during which processing and transport are repeated several times, when the strip-shaped workpiece is correctly delivered. Here, the positions of the through openings and of the shielding area of the strip-shaped workpiece change, and a change arises with certainty in the determination state of the strip-shaped workpiece by the sensors.
When the determination state of the strip-shaped workpiece changes, it is recognized that the strip-shaped workpiece is being correctly delivered. Thus, the xe2x80x9cfault reservation statexe2x80x9d is canceled and operation of the delivery reel is controlled based on the determination signals of the sensors, as is normally the case.
On the other hand, it can be imagined that, in the vicinity of the sensor located downstream, there is a barrier which shields the sensor light, or that the lower sensor is faulty when in the determination state of the strip-shaped workpiece no change occurs even with several repetitions of processing and transport. In this case, the device is considered xe2x80x9cfaultyxe2x80x9d and stopped.
A strip-shaped workpiece with through openings can be easily transported by the above described control.
(2) Additionally, in device described above in (1) for processing of a strip-shaped workpiece there is, generally, a control element which starts operation of the take-up reel when both the upper sensor and the lower sensor have determined the presence of the workpiece and which stops operation of the take-up reel when the upper sensor has determined the absence of a workpiece.
The take-up reel is controlled as follows specifically by the above described control element.
In the case in which transmission of the upper sensor and shielding of the lower sensor have been determined, in a strip-shaped workpiece with through openings there is not always a barrier in the optical path of the lower sensor, as was described above. In this case, the device is therefore not immediately considered xe2x80x9cfaultyxe2x80x9d. In this state, the rotation of the take-up reel is only started when the drive of the take-up reel has been stopped and when both the upper sensor and lower sensor have determined shielding. The rotation of the take-up reel is stopped when the upper sensor has determined transmission. In this case, the length and the position of the strip-shaped workpiece in the dip change when the strip-shaped workpiece is being transported. Thus, a case arises in which both the upper sensor and also the lower sensor determine shielding. When the sensors are shifted into this state, the take-up reel is turned and the strip-shaped workpiece is taken up.
As was described above, the transport of the strip-shaped workpiece, its delivery by a reel and its take-up onto a reel can be continued even if the strip-shaped workpiece has partial through openings, such as device holes or the like, through which sensor light passes by the measure as according to the invention that processing and transport of the strip-shaped workpiece are carried out with a preset frequency when the upper sensor has determined the absence of the workpiece and the lower sensor has determined the presence of the workpiece, these sensors being located in the transition on the side of the delivery reel, and furthermore that a fault is recognized and processing and transport are interrupted, when during the interval, during which the above described processing and the above described transport are carried out, the workpiece determination state by the above described upper sensor or the above described lower sensor does not change.
In the case in which the sensor located downstream of the dip on the side of the delivery reel due to a barrier or the like is shifted into a shielding state, or in the case in which in this sensor a fault or the like occurs, it is recognized that a fault has occurred and thus operation of the device can be stopped.
On the side of the take-up reel, the operation of the take-up reel is started only when both the upper sensor and lower sensor have determined the presence of a workpiece and furthermore, here, operation of the take-up reel is stopped when the upper sensor has determined the absence of the workpiece. In this way, the strip-shaped workpiece can be taken up without stopping operation of the device even in the case in which the sensor located downstream of the dip on the side of the take-up reel due to a barrier or the like is shifted into a shielding state, or that in this sensor a fault or the like occurs.
The invention is explained in detail below with reference to the accompanying drawings.